US20060075749A1 - Hydraulic energy intensifier - Google Patents

Hydraulic energy intensifier Download PDF

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Publication number
US20060075749A1
US20060075749A1 US10962627 US96262704A US2006075749A1 US 20060075749 A1 US20060075749 A1 US 20060075749A1 US 10962627 US10962627 US 10962627 US 96262704 A US96262704 A US 96262704A US 2006075749 A1 US2006075749 A1 US 2006075749A1
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Prior art keywords
accumulator
fluid
chamber
volume
hydraulic
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US10962627
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US7124576B2 (en )
Inventor
Mark Cherney
Daniel Radke
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Deere and Co
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Deere and Co
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    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02FDREDGING; SOIL-SHIFTING
    • E02F9/00Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20Drives; Control devices
    • E02F9/22Hydraulic or pneumatic drives
    • E02F9/2217Hydraulic or pneumatic drives with energy recovery arrangements, e.g. using accumulators, flywheels
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVO-MOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B1/00Installations or systems with accumulators; Supply reservoir or sump assemblies
    • F15B1/02Installations or systems with accumulators
    • F15B1/024Installations or systems with accumulators used as a supplementary power source, e.g. to store energy in idle periods to balance pump load
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVO-MOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B21/00Common features; Fluid-pressure systems, or details thereof, not covered by any preceding group
    • F15B21/14Energy recuperation means ; Means for reducing energy consumption
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVO-MOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/20Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/205Systems with pumps
    • F15B2211/20507Type of prime mover
    • F15B2211/20523Internal combustion engine
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVO-MOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/20Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/205Systems with pumps
    • F15B2211/2053Type of pump
    • F15B2211/20546Type of pump variable capacity
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVO-MOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/20Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/21Systems with pressure sources other than pumps, e.g. with a pyrotechnical charge
    • F15B2211/212Systems with pressure sources other than pumps, e.g. with a pyrotechnical charge the pressure sources being accumulators
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVO-MOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/60Circuit components or control therefor
    • F15B2211/605Load sensing circuits
    • F15B2211/6051Load sensing circuits having valve means between output member and the load sensing circuit
    • F15B2211/6054Load sensing circuits having valve means between output member and the load sensing circuit using shuttle valves
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVO-MOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/70Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/705Output members, e.g. hydraulic motors or cylinders or control therefor characterised by the type of output members or actuators
    • F15B2211/7051Linear output members
    • F15B2211/7053Double-acting output members
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVO-MOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00Circuits for servomotor systems
    • F15B2211/80Other types of control related to particular problems or conditions
    • F15B2211/88Control measures for saving energy

Abstract

Hydraulic circuits used to manipulate tools in, for example construction equipment, uses less power for a retraction of a hydraulic cylinder than for an extension of that cylinder. Provided is a hydraulic circuit that uses the stored energy from the low energy phase to lower the energy load on the hydraulic pump during the high energy phase. Energy from the hydraulic pump is increased during the low energy phase to increase the amount of stored hydraulic energy. The increased amount of stored energy is then used to intensify or add to the energy generated by the hydraulic pump for the high energy phase.

Description

    FIELD OF THE INVENTION
  • The invention relates to an energy recovery circuit for a hydraulic apparatus of a work vehicle such as a loader, a backhoe or the like.
  • BACKGROUND OF THE INVENTION
  • In modern work vehicles, hydraulic circuits are used to power the hydraulic cylinders that manipulate work implements. Such systems may use pumps of the variable displacement type which control the flow rate of hydraulic fluid via manipulation of their displacement volumes. A displacement control valve is used to determine the direction of fluid flow to accomplish the desired work, i.e., for example, to positively extend or retract a double acting hydraulic cylinder. The displacement control valve is also used to allow free flow of fluid so as to minimize pressure generated, i.e., to enable floating; an operating mode in which an implement rests on and follows the contours of the earth as the work vehicle is propelled along the ground.
  • When a hydraulic cylinder is used to manipulate a tool or load against a resisting force such as gravity, the hydraulic pump for the associated hydraulic system, in a vast majority of cases, generates substantially less energy in moving to a retracted position than in moving to an extended position. This is generally due to the fact that the cylinder retracts under an action of gravity, but may extend only when the hydraulic cylinder overcomes the action of gravity. Moreover, the hydraulic cylinder uses less fluid and tends to generate less force during a retraction than during an extension as the internal volume and the area of application for generating a force load on the piston are smaller on the retracting side than on the extending side of the piston. Thus a hydraulic cylinder retraction may be generally characterized as a low energy phase of the hydraulic cylinder and an extension may be generally characterized as a high energy phase of the hydraulic cylinder.
  • SUMMARY OF THE INVENTION
  • As stated earlier, in some conventional hydraulic systems for work vehicles a portion of the hydraulic energy from the low energy phase is stored for application to some other function in the work vehicle. However, in conventional work vehicles, the stored hydraulic energy is not used to lower the energy load on the hydraulic pump supplying hydraulic energy to the cylinder. Thus, in conventional work vehicles, the peak energy requirements of the high energy phase directly determine the size, capacity and energy requirements of the hydraulic pump and, thusly, the overall fuel efficiency of the hydraulic circuit.
  • Provided herein is a hydraulic circuit that uses the stored energy from the low energy phase to lower the energy load on the hydraulic pump during the high energy phase. Energy from the hydraulic pump is increased during the low energy phase to increase the amount of stored hydraulic energy. The increased amount of stored energy is then used to intensify the energy generated, by the hydraulic pump, for the high energy phase. The use of the stored energy in this manner tends to narrow the difference between the energy loads on the hydraulic pump during the low and high energy phases. This makes it possible to reduce the hydraulic pump size and benefit from increased fuel efficiency without a consequential reduction in performance for the hydraulic circuit. It also makes it possible to increase the performance of the hydraulic circuit, or reduce the size of an engine driving the hydraulic circuit, without a consequential reduction in fuel efficiency.
  • BRIEF DESCRIPTION OF THE DRAWINGS
  • Embodiments of the invention will be described in detail, with references to the following figures, wherein:
  • FIG. 1 is a view of a work vehicle in which the invention may be used; and
  • FIG. 2 is a diagram of an exemplary embodiment of the hydraulic circuit of the invention for the work vehicle in FIG. 1.
  • FIG. 3 is a diagram of another exemplary embodiment of the hydraulic circuit of the invention for the work vehicle in FIG. 1.
  • DESCRIPTION OF THE ILLUSTRATED EMBODIMENT
  • FIG. 1 illustrates a work vehicle in which the invention may be used. The particular work vehicle illustrated in FIG. 1 is an articulated four wheel drive loader 1 having a main vehicle body 10 that includes a front vehicle portion 20 pivotally connected to a rear vehicle portion 30 by vertical pivots 40, the loader being steered by pivoting of the front vehicle portion 20 relative to the rear vehicle portion 30 in a manner well known in the art. The front and rear vehicle portions 20 and 30 are respectively supported on front drive wheels 50 and rear drive wheels 60. An operator's station 70 is provided on the rear vehicle portion 30 and is generally located above the vertical pivots 40. The front vehicle portion 20 includes a boom 80, a linkage assembly 85, a work tool 90 and a hydraulic cylinder 120. The front and rear drive wheels 50 and 60 propel the vehicle along the ground and are powered in a manner well known in the art.
  • FIG. 2 illustrates a hydraulic circuit 100 representing an exemplary embodiment of the invention. The hydraulic circuit 100 illustrated includes: a load sensitive variable displacement pump 101; a shuttle check valve 102; a first displacement control valve 110; a second displacement control valve 111; an accumulator 115; an accumulator charge valve 116; an accumulator discharge valve 117; and the hydraulic cylinder 120. The load sensitive variable displacement pump 101 includes a pump inlet 101 a, a pump outlet 101 b, and a sensor inlet 101 c. The hydraulic cylinder 120 includes a first chamber 120 a, a second chamber 120 b, a cylinder rod 121, and a housing 122. The cylinder rod 121 includes a piston rod 121 a that is connected to a piston 121 b, the piston 121 b having a first application surface 121 c and a second application surface 121 d that is smaller than the first application surface 121 c by at least the cross sectional area of the connecting piston rod 121 a. The first and second chambers 120 a and 120 b include portions of the hydraulic cylinder 120 that are exposed to the first and second application surfaces 121 c and 121 d, respectively.
  • The hydraulic cylinder 120 is partially rated by an area ratio defined as the ratio of a first surface area for the first application surface 121 c to a second surface area for the second application surface 121 d. An extension load 130 represents a load on the cylinder rod 121. The extension load 130, which is encountered during an extension of the hydraulic cylinder 120, is usually greater than a retraction load 131, encountered during a retraction of the hydraulic cylinder 120.
  • The hydraulic pump 101 is fluidly connected to the first displacement control valve 110 and the second displacement control valve via the outlet 101 b. The hydraulic pump is fluidly connected to the accumulator discharge valve 117 via the inlet 101 a. The first displacement control valve 110 is in fluid communication with the first chamber 120 a and with the accumulator charge valve 116. The second displacement control valve 111 is in fluid communication with the second chamber 120 b. The accumulator 115 is in fluid communication with the accumulator charge valve 116 and the accumulator discharge valve 117. The accumulator charge valve 116 is in fluid communication with the accumulator discharge valve 117. Finally, the check valve 102 is fluidly connected to the first chamber 120 a, the second chamber 120 b and the sensor inlet 101 c via pilot lines 102 a, 102 b and 102 c respectively.
  • The first displacement control valve 110 and the second displacement control valve 111 are three position, three way valves with normally closed centers. The shuttle check valve 102 is double action in that it stops the flow of the highest of the pilot pressures from the first side 120 a and the second side 120 b and delivers the highest pilot pressure, or load sensor, to the load sensor inlet 101 c. Two single action check valves (not shown) would accomplish the same function. The accumulator charge valve 116 and the accumulator discharge valve 117 are two position, one way valves that are normally closed.
  • In operation, to extend a retracted cylinder rod 121, the hydraulic pump 101 generates a first hydraulic energy, i.e., displaces a first volume of fluid at a first pressure. As the pump generates the first hydraulic energy, the first displacement control valve 110 is moved to position #2 while the second displacement control valve 111 is shifted to position #6 and the accumulator charge valve 116 remains closed. Fluid at the first pressure then enters the first chamber 120 a and exerts the first pressure on the first application surface 121 c generating a first force greater than a second force resulting from a combination of the extension load 130 and a second hydraulic energy exerting a fluid pressure, from the weight of the fluid and any line resistance to flow, on the second application surface 121 d. The first chamber 120 a of the hydraulic cylinder 120 is then filled with fluid, extending the hydraulic cylinder 120, and forcing any fluid in the second chamber 120 b through the second displacement control valve 111, a filter assembly 142, a heat exchanger assembly 141 and into a fluid reservoir 140.
  • To retract an extended hydraulic cylinder 120, the first displacement control valve is moved to position #1, the second displacement control valve 111 is moved to position #5, the accumulator charge valve 116 is opened and the accumulator discharge valve 117 is closed. The hydraulic pump 101 then generates a second hydraulic energy, i.e., displaces a second volume of fluid at a second pressure. Fluid then enters the second chamber 120 b exerting the second pressure on the second application surface 121 d which produces a second force that, when combined with the retraction load 131, is sufficient to overcome a third force from a first chamber reaction pressure on the first application surface 121 c. The first chamber reaction pressure is produced by a reaction to the second force in combination with the retraction load 131 via, inter alia, a resistance to flow in the hydraulic lines and an accumulator reaction pressure in the accumulator 115. Fluid then flows into the second chamber 120 b, retracting the hydraulic cylinder 120 and forcing fluid out of the first chamber 120 a, through the accumulator charge valve 116 and into the accumulator 115. The accumulator 115 continues to capture pressurized fluid until a full volume of fluid is captured or the accumulator reaction pressure is equal to or greater than the first chamber reaction pressure. Thus the accumulator 115 stores a third hydraulic energy as it stores the fluid, i.e., the accumulator 115 stores the fluid from the first side 120 a under the accumulator reaction pressure.
  • If desired, a pressure transducer 150 between the first chamber 120 a and the first displacement control valve 110 may be set to signal a controller (not shown) to move the first displacement control valve 110 to position #3 and close the charge valve 116 when once the first chamber reaction pressure is reached. This allows the first chamber 120 a to be fully emptied and hydraulic cylinder to be fully retracted.
  • The pre-charge on the accumulator is usually adjusted such that the first reaction pressure will be sufficient to allow storage of the entire volume of fluid contained in the first side 120 a of the hydraulic cylinder 120 with the cylinder rod 121 fully extended. However, the accumulator 115 may be pre-charged to higher pressures requiring the hydraulic pump 101 to generate higher second pressures. Additionally, the pre-charge may be adjusted to allow only a certain or pre-defined volume of fluid to be stored in the accumulator 115. Naturally, in this embodiment, a higher pre-charge on the accumulator allows a greater amount of hydraulic energy to be stored in the accumulator 115 as hydraulic energy is a function of pressure and volume.
  • During the next extension of the cylinder rod 121, the accumulator discharge valve 117 is opened to release the third hydraulic energy stored in the accumulator 115 and apply the accumulator reaction pressure to the pump inlet 101 a of the hydraulic pump 101 to reduce the pressure differential between the pump inlet 101 a and the pump outlet 101 b and, consequently, reduce the demand on the hydraulic pump 101 during the extension. This results in a decrease in the peak demand on the hydraulic pump 101. It also tends to level all demands on the hydraulic pump 101 for extending and retracting the hydraulic cylinder 120 and could lead to a decrease in the size and energy requirements of the engine (not shown) without a consequential loss in performance for the hydraulic circuit 100.
  • All valve operations, including those of the accumulator charge valve 116 and the accumulator discharge valve 117, result from electrical signals that are automatically generated as the controls for functioning the hydraulic cylinder 120 are manipulated.
  • A maximum reduction in peak demand and, consequently, an optimal leveling of all demands on the hydraulic pump 101 as well as a reduction in size of the engine (not shown) may be accomplished by adjusting the pre-charge on the accumulator 115 to require the maximum second hydraulic energy to be approximately equal to the maximum first hydraulic energy. Such could, for example, be accomplished by choosing the maximum load 130 the hydraulic cylinder 120 will handle, determining the retraction load 131 the hydraulic circuit will experience on retraction of the hydraulic cylinder 120, ascertaining the area ratio of the hydraulic cylinder 120, and pre-charging the accumulator accordingly. For example, the pre-charge may be adjusted such that H2max/AR+HG≅H1max, where H2max is the maximum second hydraulic energy, AR is the area ratio, HG is a hydraulic energy produced by the action of gravity, H1max is the maximum first hydraulic energy, and H2max ≅H1max. Under these circumstances, (P2maxA2+FRG)/A1 >=PRAmax, where P2max is the second pressure, A2 is the second surface area, FRG is the force from the action of gravity, A1 is the first surface area, and PRAmax is the accumulator reaction pressure.
  • Work tool float is accomplished by moving the first and second displacement control valves 110 and 111 to positions #3 and #6 respectively. This allows fluid to freely flow between the reservoir and the chambers 120 a and 120 b.
  • FIG. 3 illustrates another hydraulic circuit 200 as an exemplary embodiment of the invention in which the accumulator charge valve 116 and the accumulator discharge valve 117 are replaced by a single accumulator valve 210. The accumulator valve 210 is moved to a charge position #7 when the accumulator 115 is being filled with fluid from the first chamber 120 a. The accumulator valve 210 is then moved to charge position #8 once the accumulator 115 is charged. Finally the accumulator valve 210 is moved to position #9 to release the fluid stored in the accumulator 115 at the accumulator reaction pressure and apply it to the pump inlet 101 a of the hydraulic pump 101.
  • Having described the illustrated embodiment, it will become apparent that various modifications can be made without departing from the scope of the invention.

Claims (35)

1. A hydraulic energy intensifying circuit for a work vehicle, the work vehicle including a frame, a tool, a linkage between the frame and the tool, a boom between the frame and the tool, a hydraulic cylinder to manipulate the tool, the hydraulic cylinder having a first chamber and a second chamber, the hydraulic cylinder extending against a first load under an application of a first volume of fluid at a first pressure to the first chamber, the hydraulic cylinder retracting under a second load and an application of a second volume of fluid at a second pressure to the second chamber, a first chamber reaction pressure being produced in the first chamber when the hydraulic cylinder is retracting, the hydraulic energy intensifying circuit comprising:
a hydraulic pump to displace the first volume of fluid at the first pressure and the second volume of fluid at the second pressure, the hydraulic pump having a pump inlet;
at least one displacement control valve to direct the first volume of fluid to the first chamber to extend the cylinder rod and the second volume of fluid to the second chamber to retract the cylinder rod on demand, the at least one displacement control valve capable of blocking fluid flow from the first chamber;
an accumulator capable of storing a predefined volume of fluid from the first chamber of the hydraulic cylinder under an accumulator reaction pressure, the predefined volume being determined when the hydraulic cylinder is in an extended position, the accumulator being pre-charged to a first pre-charge pressure that allows the predefined volume of fluid to be stored in the accumulator when the second volume of fluid at the second pressure is applied to the second chamber in combination with the second load;
at least one accumulator valve to allow the predefined volume of fluid from the first chamber to be stored in the accumulator, the at least one accumulator valve allowing the fluid stored in the accumulator under the accumulator reaction pressure to be released from the accumulator, the at least one displacement control valve directing the second volume of fluid from the hydraulic pump to the second chamber and blocking the fluid flow from the first chamber to, thereby, divert the fluid flow from the first chamber to the at least one accumulator valve, the at least one accumulator valve opening to allow the predefined volume of fluid from the first chamber to be stored in the accumulator, the accumulator storing the predefined volume of fluid at the accumulator reaction pressure.
2. The hydraulic energy intensifying circuit of claim 1, wherein the at least one accumulator valve comprises:
an accumulator charge valve to allow the fluid from the first chamber to be stored in the accumulator; and
an accumulator discharge valve to allow the fluid stored in the accumulator under the accumulator reaction pressure to be released from the accumulator; the at least one displacement control valve directing the second volume of fluid from the hydraulic pump to the second chamber and blocking the fluid flow from the first chamber to, thereby, divert the fluid from the first chamber to the at least one accumulator valve, the at least one accumulator valve opening to allow the predetermined volume of fluid from the first chamber to be stored in the accumulator, the accumulator storing the predefined volume of fluid at the accumulator reaction pressure.
3. The hydraulic energy intensifying circuit of claim 1, wherein the at least one displacement control valve comprises a first displacement control valve and a second displacement control valve, the first displacement control valve directing the first hydraulic energy to the first chamber, the second displacement control valve directing the second hydraulic energy to the second chamber.
4. The hydraulic energy intensifying circuit of claim 1, wherein the hydraulic pump is a load sensitive variable displacement hydraulic pump having a load sensor.
5. The hydraulic energy intensifying circuit of claim 4, further comprising means for delivering a load sense of a first hydraulic pressure on the first chamber and a second hydraulic pressure on the second chamber to the load sensor.
6. The hydraulic energy intensifying circuit of claim 5, wherein the means for delivering the load sense comprises a shuttle check valve.
7. The hydraulic energy intensifying circuit of claim 5, wherein the second load is a retraction load resulting from an action of gravity.
8. The hydraulic energy intensifying circuit of claim 5, wherein the first pressure is the highest pilot pressure.
9. The hydraulic energy intensifying circuit of claim 5, wherein the second pressure is the load sense.
10. The hydraulic energy intensifying circuit of claim 2, wherein the accumulator discharge valve opens to release the predefined volume of fluid stored in the accumulator.
11. The hydraulic energy intensifying circuit of claim 10 wherein the accumulator reaction pressure is applied to the pump inlet to reduce a load on the pump.
12. A hydraulic energy intensifying circuit, comprising:
a hydraulic cylinder to manipulate a first load and a second load, the hydraulic cylinder a having a first chamber, a second chamber and a cylinder rod, the cylinder rod having a piston and a piston rod, the piston having a first application surface and a second application surface, the hydraulic cylinder extending against the first load under an application of a first volume of fluid at a first pressure to the first chamber, the first pressure producing a first force as the first pressure is applied against the first application surface, the hydraulic cylinder retracting under a second load and an application of a second volume of fluid at a second pressure to the second chamber, the second pressure producing a second force as the second pressure is applied against the second application surface, a first chamber reaction pressure being produced in the first chamber when the hydraulic cylinder is retracting;
a hydraulic pump to generate the first volume of fluid at the first pressure and the second volume at the second pressure, the hydraulic pump having a pump inlet;
at least one displacement control valve to direct the first volume of fluid at the first pressure to the first chamber and the second volume of fluid at the second pressure to the second chamber, the at least one displacement control valve capable of blocking fluid flow from the first chamber;
an accumulator capable of storing a predefined volume of fluid from the first chamber at an accumulator reaction pressure, the accumulator being pre-charged to a first pressure that allows the predefined volume of fluid to be stored in the accumulator only under the first chamber reaction pressure produced when at least one of the second force is greater than the second load and the second hydraulic energy is applied in combination with the second load;
at least one accumulator valve to allow the predefined volume of fluid to be stored in the accumulator under the first chamber reaction pressure, the at least one accumulator valve allowing the predefined volume of fluid to be released from the accumulator on demand, the at least one displacement control valve directing the second volume of fluid from the hydraulic pump to the second chamber and blocking the fluid flow from the first chamber to, thereby, divert the fluid from the first chamber to the at least one accumulator valve, the at least one accumulator valve opening to allow the predefined volume of fluid from the first chamber to be stored in the accumulator, the accumulator storing the predefined volume of fluid at the accumulator reaction pressure.
13. The hydraulic energy intensifying circuit of claim 1, wherein the at least one accumulator valve comprises:
an accumulator charge valve to allow the fluid from the first chamber to be stored in the accumulator; and
an accumulator discharge valve to allow the fluid stored in the accumulator under the accumulator reaction pressure to be released from the accumulator; the at least one displacement control valve directing the second volume of fluid from the hydraulic pump to the second chamber and blocking the fluid flow from the first chamber to, thereby, divert the fluid from the first chamber to the at least one accumulator valve, the at least one accumulator charge valve opening to allow the predefined volume of fluid from the first chamber to be stored in the accumulator, the accumulator discharge valve being closed, the accumulator storing the predefined volume of fluid at the accumulator reaction pressure.
14. The hydraulic energy intensifying circuit of claim 12, wherein the at least one displacement control valve comprises a first displacement control valve and a second displacement control valve, the first displacement control valve directing the first volume of fluid to the first chamber, the second displacement control valve directing the second volume of fluid to the second chamber.
15. The hydraulic energy intensifying circuit of claim 12, wherein the hydraulic pump is a load sensitive variable displacement hydraulic pump having a load sensor.
16. The hydraulic energy intensifying circuit of claim 15, further comprising means for delivering a load sense of a first hydraulic pressure at the first chamber and a second hydraulic pressure at the second chamber to the load sensor.
17. The hydraulic energy intensifying circuit of claim 16, wherein the means for delivering the load sense comprises a shuttle check valve.
18. The hydraulic energy intensifying circuit of claim 16, wherein the second load is a retraction load resulting from an action of gravity.
19. The hydraulic energy intensifying circuit of claim 16, wherein the first pressure is greater than the load sense.
20. The hydraulic energy intensifying circuit of claim 16, wherein the second a pressure is greater than the load sense
21. The hydraulic energy intensifying circuit of claim 13, wherein the accumulator discharge valve opens to release the predefined volume of fluid stored in the accumulator.
22. The hydraulic energy intensifying circuit of claim 21 wherein the accumulator reaction pressure is applied to the pump inlet to reduce a load on the pump.
23. A method of intensifying energy in a hydraulic circuit for a work vehicle, the hydraulic circuit including a hydraulic cylinder to manipulate a load, the hydraulic cylinder having a first chamber and a second chamber, the hydraulic cylinder extending against a first load under an application of a first volume of fluid at a first pressure to the first chamber, the hydraulic cylinder retracting under a second load and a second force produced by an application of a second volume of fluid at a second pressure to the second chamber, a first chamber reaction pressure being produced in the first chamber when the hydraulic cylinder is retracting, a hydraulic pump to displace the first volume of fluid at the first pressure and the second volume of fluid at the second pressure, the hydraulic pump having a pump inlet, at least one displacement control valve to direct the first volume of fluid to the first chamber and the second volume of fluid to the second chamber on demand, an accumulator capable of storing a predefined volume of fluid at an accumulator reaction pressure, an accumulator charge valve to allow the predefined volume of fluid to be stored in the accumulator, an accumulator discharge valve to allow the predefined volume of fluid to be released from the accumulator, the method comprising:
pre-charging the accumulator to a first pressure that allows the pre-defined volume of fluid to be stored in the accumulator under the first chamber reaction pressure produced when at least one of the second force is greater than the second load and the second hydraulic energy is applied in combination with the second load;
displacing the second volume of fluid at the second pressure with the hydraulic pump;
opening the at least one displacement control valve to the second chamber to direct the second volume of fluid to the second chamber while closing the at least one displacement control valve to the first chamber to divert fluid flow from the first chamber to the accumulator charge valve; and
opening the accumulator charge valve to allow the accumulator to store the pre-defined volume of fluid at the accumulator reaction pressure, the accumulator discharge valve being closed.
24. The method of claim 23, further comprising closing the accumulator charge valve after the pre-defined volume of fluid is stored in the accumulator.
25. The method of claim 24, further comprising:
opening the accumulator discharge valve at a time of high demand for hydraulic energy to release the predefined volume of fluid stored in the accumulator; and
applying the accumulator reaction pressure to the pump inlet to reduce a load on the hydraulic pump.
26. The method of claim 23, wherein the second load is a retraction load resulting from an action of gravity.
27. A method of intensifying energy in a hydraulic circuit for a work vehicle, the hydraulic circuit including a hydraulic cylinder to manipulate a load, the hydraulic cylinder having a first chamber and a second chamber, the hydraulic cylinder extending against a first load under an application of a first volume of fluid at a first pressure to the first chamber, the hydraulic cylinder retracting under a second load and an application of a second volume of fluid at a second pressure to the second chamber, a first chamber reaction pressure being produced in the first chamber when the cylinder rod is retracting, a hydraulic pump to displace the first volume of fluid at the first pressure and the second volume of fluid at the second pressure, the hydraulic pump having a pump inlet, at least one displacement control valve to direct the first volume of fluid to the first chamber and the second volume of fluid to the second chamber on demand, an accumulator capable of storing a predefined volume of fluid form the first chamber at an accumulator reaction pressure, an accumulator charge valve to allow the predefined volume of fluid to be stored in the accumulator, an accumulator discharge valve to allow the predefined volume of fluid to be released from the accumulator, the method comprising:
pre-charging the accumulator to a pre-charge pressure that allows the pre-defined volume of fluid to be stored in the accumulator under the first chamber reaction pressure produced when the second hydraulic energy and the second load are applied;
generating the second volume of fluid at the second pressure with the hydraulic pump;
opening the at least one displacement control valve to the second chamber to direct the volume of fluid to the second chamber while closing the at.least one displacement control valve to the first chamber to divert fluid flow from the first chamber to the accumulator charge valve; and
opening the accumulator charge valve to allow the accumulator to store the pre-defined volume of fluid at the accumulator reaction pressure, the accumulator discharge valve being closed.
28. The method of claim 27, further comprising closing the accumulator charge valve after the pre-defined volume of fluid is stored in the accumulator.
29. The method of claim 28, further comprising:
opening the accumulator discharge valve at a time of high demand for hydraulic energy to release the third hydraulic energy stored in the accumulator; and
applying the accumulator reaction pressure to the pump inlet to reduce a load on the hydraulic pump.
30. The method of claim 27, wherein the second load is a retraction load resulting from an action of gravity.
31. The hydraulic energy intensifying circuit of claim 1, wherein the predefined volume of fluid is a full volume of fluid contained in the first chamber of the hydraulic cylinder at a fully extended position.
32. The hydraulic energy intensifying circuit of claim 12, wherein the predefined volume of fluid is a full volume of fluid contained in the first chamber of the hydraulic cylinder at a fully extended position.
33. The method of claim 23, wherein the predefined volume of fluid is a full volume of fluid contained in the first chamber of the hydraulic cylinder at a fully extended position.
34. The method of claim 27, wherein the predefined volume of fluid is a full volume of fluid contained in the first chamber of the hydraulic cylinder at a fully extended position.
35. The method of claim 24, further comprising:
opening the accumulator discharge valve at a time of high demand for hydraulic energy to release the predefined volume of fluid stored in the accumulator; and
applying the accumulator reaction pressure to reduce a load on the hydraulic pump.
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Cited By (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20080110165A1 (en) * 2006-11-14 2008-05-15 Hamkins Eric P Energy recovery and reuse methods for a hydraulic system
US20080110166A1 (en) * 2006-11-14 2008-05-15 Stephenson Dwight B Energy recovery and reuse techniques for a hydraulic system
EP2039945A1 (en) * 2006-07-10 2009-03-25 Caterpillar Japan Ltd. Hydraulic control system for working machine
US20090282822A1 (en) * 2008-04-09 2009-11-19 Mcbride Troy O Systems and Methods for Energy Storage and Recovery Using Compressed Gas
US7802426B2 (en) 2008-06-09 2010-09-28 Sustainx, Inc. System and method for rapid isothermal gas expansion and compression for energy storage
US7958731B2 (en) 2009-01-20 2011-06-14 Sustainx, Inc. Systems and methods for combined thermal and compressed gas energy conversion systems
US7963110B2 (en) 2009-03-12 2011-06-21 Sustainx, Inc. Systems and methods for improving drivetrain efficiency for compressed gas energy storage
US8037678B2 (en) 2009-09-11 2011-10-18 Sustainx, Inc. Energy storage and generation systems and methods using coupled cylinder assemblies
US8046990B2 (en) 2009-06-04 2011-11-01 Sustainx, Inc. Systems and methods for improving drivetrain efficiency for compressed gas energy storage and recovery systems
US8104274B2 (en) 2009-06-04 2012-01-31 Sustainx, Inc. Increased power in compressed-gas energy storage and recovery
US8117842B2 (en) 2009-11-03 2012-02-21 Sustainx, Inc. Systems and methods for compressed-gas energy storage using coupled cylinder assemblies
US8171728B2 (en) 2010-04-08 2012-05-08 Sustainx, Inc. High-efficiency liquid heat exchange in compressed-gas energy storage systems
US8191362B2 (en) 2010-04-08 2012-06-05 Sustainx, Inc. Systems and methods for reducing dead volume in compressed-gas energy storage systems
US8225606B2 (en) 2008-04-09 2012-07-24 Sustainx, Inc. Systems and methods for energy storage and recovery using rapid isothermal gas expansion and compression
US8234863B2 (en) 2010-05-14 2012-08-07 Sustainx, Inc. Forming liquid sprays in compressed-gas energy storage systems for effective heat exchange
US8240140B2 (en) 2008-04-09 2012-08-14 Sustainx, Inc. High-efficiency energy-conversion based on fluid expansion and compression
US8250863B2 (en) 2008-04-09 2012-08-28 Sustainx, Inc. Heat exchange with compressed gas in energy-storage systems
US8359856B2 (en) 2008-04-09 2013-01-29 Sustainx Inc. Systems and methods for efficient pumping of high-pressure fluids for energy storage and recovery
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US8448433B2 (en) 2008-04-09 2013-05-28 Sustainx, Inc. Systems and methods for energy storage and recovery using gas expansion and compression
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US8479505B2 (en) 2008-04-09 2013-07-09 Sustainx, Inc. Systems and methods for reducing dead volume in compressed-gas energy storage systems
US8495872B2 (en) 2010-08-20 2013-07-30 Sustainx, Inc. Energy storage and recovery utilizing low-pressure thermal conditioning for heat exchange with high-pressure gas
WO2012054344A3 (en) * 2010-10-18 2013-08-15 Eaton Corporation Hydraulic drive circuit with parallel architectured accumulator
US8539763B2 (en) 2011-05-17 2013-09-24 Sustainx, Inc. Systems and methods for efficient two-phase heat transfer in compressed-air energy storage systems
US8578708B2 (en) 2010-11-30 2013-11-12 Sustainx, Inc. Fluid-flow control in energy storage and recovery systems
US8667792B2 (en) 2011-10-14 2014-03-11 Sustainx, Inc. Dead-volume management in compressed-gas energy storage and recovery systems
US8677744B2 (en) 2008-04-09 2014-03-25 SustaioX, Inc. Fluid circulation in energy storage and recovery systems
CN103672126A (en) * 2013-12-26 2014-03-26 重庆川仪自动化股份有限公司 Electro-hydraulic actuator
US8991167B2 (en) 2010-10-15 2015-03-31 Eaton Corporation Hybrid hydraulic systems for industrial processes

Families Citing this family (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7269944B2 (en) * 2005-09-30 2007-09-18 Caterpillar Inc. Hydraulic system for recovering potential energy
JP5626712B2 (en) * 2007-04-23 2014-11-19 フスコ インターナショナル インコーポレイテッドHusco International, Inc. Energy recovery and recycling techniques for hydraulic system
US20090025379A1 (en) * 2007-07-24 2009-01-29 Parker-Hannifin Corporation System for recovering energy from a hydraulic lift
DE602008004099D1 (en) * 2008-04-29 2011-02-03 Parker Hannifin Ab Arrangement to operate a hydraulic device
JP5354650B2 (en) * 2008-10-22 2013-11-27 キャタピラー エス エー アール エル Hydraulic control system in the working machine
US8186154B2 (en) * 2008-10-31 2012-05-29 Caterpillar Inc. Rotary flow control valve with energy recovery
DE102009053618A1 (en) * 2009-11-17 2011-05-19 Robert Bosch Gmbh Hydraulic drive with energy recovery
CN101843957B (en) * 2010-05-25 2012-01-11 武汉科技大学 Reciprocating hydraulic slow drop device
US9139982B2 (en) 2011-06-28 2015-09-22 Caterpillar Inc. Hydraulic control system having swing energy recovery
US8919113B2 (en) 2011-06-28 2014-12-30 Caterpillar Inc. Hydraulic control system having energy recovery kit
US8776511B2 (en) 2011-06-28 2014-07-15 Caterpillar Inc. Energy recovery system having accumulator and variable relief
US8850806B2 (en) 2011-06-28 2014-10-07 Caterpillar Inc. Hydraulic control system having swing motor energy recovery
US9068575B2 (en) 2011-06-28 2015-06-30 Caterpillar Inc. Hydraulic control system having swing motor energy recovery
US8858151B2 (en) * 2011-08-16 2014-10-14 Caterpillar Inc. Machine having hydraulically actuated implement system with down force control, and method
CN104254694B (en) 2012-01-05 2017-05-10 派克汉尼芬公司 Electro-hydraulic system with a float function
EP2662142B1 (en) * 2012-05-10 2015-11-18 Sandvik Intellectual Property AB Hydraulic system for controlling a jaw crusher
DE102012107699B3 (en) * 2012-08-22 2014-01-02 Parker Hannifin Manufacturing Germany GmbH & Co. KG Body mass drive with hydraulic energy recovery circuit
US9091286B2 (en) 2012-08-31 2015-07-28 Caterpillar Inc. Hydraulic control system having electronic flow limiting
US9388829B2 (en) 2012-08-31 2016-07-12 Caterpillar Inc. Hydraulic control system having swing motor energy recovery
US9388828B2 (en) 2012-08-31 2016-07-12 Caterpillar Inc. Hydraulic control system having swing motor energy recovery
US9187878B2 (en) 2012-08-31 2015-11-17 Caterpillar Inc. Hydraulic control system having swing oscillation dampening
US9145660B2 (en) 2012-08-31 2015-09-29 Caterpillar Inc. Hydraulic control system having over-pressure protection
US9086081B2 (en) 2012-08-31 2015-07-21 Caterpillar Inc. Hydraulic control system having swing motor recovery
US9328744B2 (en) 2012-08-31 2016-05-03 Caterpillar Inc. Hydraulic control system having swing energy recovery
KR101825753B1 (en) * 2012-09-25 2018-02-05 현대건설기계 주식회사 Boom down energy regeneration system
DE102013101107A1 (en) * 2013-02-05 2014-08-07 Karlsruher Institut für Technologie More hydraulic load system with energy-efficient hydraulic circuit
WO2015019839A1 (en) * 2013-08-05 2015-02-12 住友重機械工業株式会社 Shovel
FR3011047B1 (en) * 2013-09-20 2015-11-13 Commissariat Energie Atomique Device hydraulically operated IMPROVED ENERGY CONSUMPTION
US20170211597A1 (en) * 2014-04-04 2017-07-27 Volvo Construction Equipment Ab Hydraulic system and method for controlling an implement of a working machine
WO2017018557A1 (en) * 2015-07-28 2017-02-02 볼보 컨스트럭션 이큅먼트 에이비 Hydraulic circuit for construction machine

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4646518A (en) * 1983-07-15 1987-03-03 Mannesmann Rexroth Gmbh Driving unit for a feed pump
US5046309A (en) * 1990-01-22 1991-09-10 Shin Caterpillar Mitsubishi Ltd. Energy regenerative circuit in a hydraulic apparatus
US6584769B1 (en) * 1998-06-27 2003-07-01 Lars Bruun Mobile working machine
US6655136B2 (en) * 2001-12-21 2003-12-02 Caterpillar Inc System and method for accumulating hydraulic fluid
US6739127B2 (en) * 2002-06-07 2004-05-25 Caterpillar Inc Hydraulic system pump charging and recirculation apparatus
US6748738B2 (en) * 2002-05-17 2004-06-15 Caterpillar Inc. Hydraulic regeneration system
US20050066655A1 (en) * 2003-09-26 2005-03-31 Aarestad Robert A. Cylinder with internal pushrod

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6434864B1 (en) * 2000-09-22 2002-08-20 Grigoriy Epshteyn Frontal loader
US7269944B2 (en) * 2005-09-30 2007-09-18 Caterpillar Inc. Hydraulic system for recovering potential energy

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4646518A (en) * 1983-07-15 1987-03-03 Mannesmann Rexroth Gmbh Driving unit for a feed pump
US5046309A (en) * 1990-01-22 1991-09-10 Shin Caterpillar Mitsubishi Ltd. Energy regenerative circuit in a hydraulic apparatus
US6584769B1 (en) * 1998-06-27 2003-07-01 Lars Bruun Mobile working machine
US6655136B2 (en) * 2001-12-21 2003-12-02 Caterpillar Inc System and method for accumulating hydraulic fluid
US6748738B2 (en) * 2002-05-17 2004-06-15 Caterpillar Inc. Hydraulic regeneration system
US6739127B2 (en) * 2002-06-07 2004-05-25 Caterpillar Inc Hydraulic system pump charging and recirculation apparatus
US20050066655A1 (en) * 2003-09-26 2005-03-31 Aarestad Robert A. Cylinder with internal pushrod

Cited By (56)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2039945A1 (en) * 2006-07-10 2009-03-25 Caterpillar Japan Ltd. Hydraulic control system for working machine
EP2039945A4 (en) * 2006-07-10 2011-05-04 Caterpillar Sarl Hydraulic control system for working machine
US20080110165A1 (en) * 2006-11-14 2008-05-15 Hamkins Eric P Energy recovery and reuse methods for a hydraulic system
US20080110166A1 (en) * 2006-11-14 2008-05-15 Stephenson Dwight B Energy recovery and reuse techniques for a hydraulic system
US7905088B2 (en) 2006-11-14 2011-03-15 Incova Technologies, Inc. Energy recovery and reuse techniques for a hydraulic system
US7823379B2 (en) 2006-11-14 2010-11-02 Husco International, Inc. Energy recovery and reuse methods for a hydraulic system
US8225606B2 (en) 2008-04-09 2012-07-24 Sustainx, Inc. Systems and methods for energy storage and recovery using rapid isothermal gas expansion and compression
US7832207B2 (en) 2008-04-09 2010-11-16 Sustainx, Inc. Systems and methods for energy storage and recovery using compressed gas
US20110056193A1 (en) * 2008-04-09 2011-03-10 Mcbride Troy O Systems and methods for energy storage and recovery using compressed gas
US8479505B2 (en) 2008-04-09 2013-07-09 Sustainx, Inc. Systems and methods for reducing dead volume in compressed-gas energy storage systems
US20090282822A1 (en) * 2008-04-09 2009-11-19 Mcbride Troy O Systems and Methods for Energy Storage and Recovery Using Compressed Gas
US8359856B2 (en) 2008-04-09 2013-01-29 Sustainx Inc. Systems and methods for efficient pumping of high-pressure fluids for energy storage and recovery
US8250863B2 (en) 2008-04-09 2012-08-28 Sustainx, Inc. Heat exchange with compressed gas in energy-storage systems
US8763390B2 (en) 2008-04-09 2014-07-01 Sustainx, Inc. Heat exchange with compressed gas in energy-storage systems
US7900444B1 (en) 2008-04-09 2011-03-08 Sustainx, Inc. Systems and methods for energy storage and recovery using compressed gas
US8240140B2 (en) 2008-04-09 2012-08-14 Sustainx, Inc. High-efficiency energy-conversion based on fluid expansion and compression
US8733095B2 (en) 2008-04-09 2014-05-27 Sustainx, Inc. Systems and methods for efficient pumping of high-pressure fluids for energy
US8733094B2 (en) 2008-04-09 2014-05-27 Sustainx, Inc. Systems and methods for energy storage and recovery using rapid isothermal gas expansion and compression
US8627658B2 (en) 2008-04-09 2014-01-14 Sustainx, Inc. Systems and methods for energy storage and recovery using rapid isothermal gas expansion and compression
US8713929B2 (en) 2008-04-09 2014-05-06 Sustainx, Inc. Systems and methods for energy storage and recovery using compressed gas
US8677744B2 (en) 2008-04-09 2014-03-25 SustaioX, Inc. Fluid circulation in energy storage and recovery systems
US8209974B2 (en) 2008-04-09 2012-07-03 Sustainx, Inc. Systems and methods for energy storage and recovery using compressed gas
US8474255B2 (en) 2008-04-09 2013-07-02 Sustainx, Inc. Forming liquid sprays in compressed-gas energy storage systems for effective heat exchange
US8448433B2 (en) 2008-04-09 2013-05-28 Sustainx, Inc. Systems and methods for energy storage and recovery using gas expansion and compression
US7802426B2 (en) 2008-06-09 2010-09-28 Sustainx, Inc. System and method for rapid isothermal gas expansion and compression for energy storage
US8240146B1 (en) 2008-06-09 2012-08-14 Sustainx, Inc. System and method for rapid isothermal gas expansion and compression for energy storage
US8234862B2 (en) 2009-01-20 2012-08-07 Sustainx, Inc. Systems and methods for combined thermal and compressed gas energy conversion systems
US8122718B2 (en) 2009-01-20 2012-02-28 Sustainx, Inc. Systems and methods for combined thermal and compressed gas energy conversion systems
US7958731B2 (en) 2009-01-20 2011-06-14 Sustainx, Inc. Systems and methods for combined thermal and compressed gas energy conversion systems
US7963110B2 (en) 2009-03-12 2011-06-21 Sustainx, Inc. Systems and methods for improving drivetrain efficiency for compressed gas energy storage
US8234868B2 (en) 2009-03-12 2012-08-07 Sustainx, Inc. Systems and methods for improving drivetrain efficiency for compressed gas energy storage
US8104274B2 (en) 2009-06-04 2012-01-31 Sustainx, Inc. Increased power in compressed-gas energy storage and recovery
US8046990B2 (en) 2009-06-04 2011-11-01 Sustainx, Inc. Systems and methods for improving drivetrain efficiency for compressed gas energy storage and recovery systems
US8479502B2 (en) 2009-06-04 2013-07-09 Sustainx, Inc. Increased power in compressed-gas energy storage and recovery
US8468815B2 (en) 2009-09-11 2013-06-25 Sustainx, Inc. Energy storage and generation systems and methods using coupled cylinder assemblies
US8037678B2 (en) 2009-09-11 2011-10-18 Sustainx, Inc. Energy storage and generation systems and methods using coupled cylinder assemblies
US8109085B2 (en) 2009-09-11 2012-02-07 Sustainx, Inc. Energy storage and generation systems and methods using coupled cylinder assemblies
US8117842B2 (en) 2009-11-03 2012-02-21 Sustainx, Inc. Systems and methods for compressed-gas energy storage using coupled cylinder assemblies
US8245508B2 (en) 2010-04-08 2012-08-21 Sustainx, Inc. Improving efficiency of liquid heat exchange in compressed-gas energy storage systems
US8171728B2 (en) 2010-04-08 2012-05-08 Sustainx, Inc. High-efficiency liquid heat exchange in compressed-gas energy storage systems
US8661808B2 (en) 2010-04-08 2014-03-04 Sustainx, Inc. High-efficiency heat exchange in compressed-gas energy storage systems
US8191362B2 (en) 2010-04-08 2012-06-05 Sustainx, Inc. Systems and methods for reducing dead volume in compressed-gas energy storage systems
US8234863B2 (en) 2010-05-14 2012-08-07 Sustainx, Inc. Forming liquid sprays in compressed-gas energy storage systems for effective heat exchange
US8495872B2 (en) 2010-08-20 2013-07-30 Sustainx, Inc. Energy storage and recovery utilizing low-pressure thermal conditioning for heat exchange with high-pressure gas
US8991167B2 (en) 2010-10-15 2015-03-31 Eaton Corporation Hybrid hydraulic systems for industrial processes
US9874233B2 (en) 2010-10-15 2018-01-23 Eaton Corporation Hybrid hydraulic systems for industrial processes
US9346207B2 (en) 2010-10-18 2016-05-24 Eaton Corporation Hydraulic drive circuit with parallel architectured accumulator
WO2012054344A3 (en) * 2010-10-18 2013-08-15 Eaton Corporation Hydraulic drive circuit with parallel architectured accumulator
EP2638293B1 (en) 2010-10-18 2017-07-05 Eaton Corporation Hydraulic drive circuit with parallel architectured accumulator
CN103459848A (en) * 2010-10-18 2013-12-18 伊顿公司 Hydraulic drive circuit with parallel architectured accumulator
US8578708B2 (en) 2010-11-30 2013-11-12 Sustainx, Inc. Fluid-flow control in energy storage and recovery systems
US8806866B2 (en) 2011-05-17 2014-08-19 Sustainx, Inc. Systems and methods for efficient two-phase heat transfer in compressed-air energy storage systems
US8539763B2 (en) 2011-05-17 2013-09-24 Sustainx, Inc. Systems and methods for efficient two-phase heat transfer in compressed-air energy storage systems
US8667792B2 (en) 2011-10-14 2014-03-11 Sustainx, Inc. Dead-volume management in compressed-gas energy storage and recovery systems
CN103115028A (en) * 2013-03-12 2013-05-22 北京机械设备研究所 Electro-hydraulic servo actuator
CN103672126A (en) * 2013-12-26 2014-03-26 重庆川仪自动化股份有限公司 Electro-hydraulic actuator

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